Number of infectious adults has dropped by a third since last month

The results of the recently completed wave of the study on the prevalence of the coronavirus in Estonia led by the University of Tartu show that the easing of restrictions at the beginning of May has not led to a new increase in the number of infectious adults. According to the study, one in 280 adults is infectious, and antibodies against coronavirus have developed in half of adults.

During the study wave from 13 to 24 May, 2,377 adult subjects were tested. Of these, 28 tested positive, only nine of whom could be considered infectious. The remaining 19 had already recovered from coronavirus and were no longer infectious. This means that an average of 0.38% of the adult population can be infectious at present, that is about 3,900 people. This is down by a third compared to the study wave conducted in April.

The leader of the prevalence study, Professor of Family Medicine of the University of Tartu Ruth Kalda said the current coronavirus situation is comparable to that of the beginning of November last year. The only difference is that in November, the infection rates were rising, while the current trend is clearly the opposite. “The fact that the easing of restrictions at the beginning of the month has not changed this trend is a good example of how society can be gradually re-opened if precautions are carefully followed,” Kalda said.

Every second adult has antibodies

As a part of the prevalence study, 2,290 subjects were tested for coronavirus antibodies, half of whom (49.5%) had developed antibodies. This suggests that around a half of the adult population, i.e. 530,800 people on average, has coronavirus antibodies. Most often, antibodies have been acquired by vaccination with one or two doses of vaccine.

Antibody prevalence was the highest (80%) among people over 65. Slightly more than half of 40–64-year-olds have antibodies, compared with slightly less than a third in the 18–39 age group. Kalda explained that, according to the study, almost all people have developed antibodies after two doses of vaccine. According to Kalda, this gives hope that by continuing at the same rate, we could achieve the level of vaccination that supports the safety of society by autumn. “This mostly depends on people’s continuing willingness to be vaccinated and their readiness to follow the precautions also during summer, despite the easing of restrictions,” Kalda explained.

Close contacts with the infected are decreasing

The behavioural analysis of the prevalence study confirms that along with the level of infections, also the potential close contacts with infected people have decreased. At the peak of the epidemic, one in ten people had been in contact with a coronavirus-infected person, now it is only one in 25. Along with the easing of restrictions in society, people’s sense of danger has also somewhat diminished. Thus, the proportion of those who do not change anything in their behaviour after a potential close contact has been continuously increasing since March (38%).

The study on the prevalence of coronavirus is carried out by a broad-based research group of the University of Tartu in cooperation with Synlab Eesti, Medicum and Kantar Emor.
For more information about the study, see the University of Tartu web page.

Further information: Ruth Kalda, Head of the Institute of Family Medicine and Public Health, Professor of Family Medicine, 5698 5599,